
function  
SlkError ( tokens )
{
                         
this.mismatch = function ( terminal, token )
{
    console.log ( "  expecting " + GetSymbolName ( terminal ) +
                   " but found " + GetSymbolName ( token ) );
    return  token;
}

this.no_entry = function ( nonterminal, token, level )
{
    console.log ( "  syntax error: skipping input " + GetSymbolName ( token ) );
    token = tokens.get();                       // advance the input

    return  token;
}

this.input_left = function()
{
}

this.message = function( message )
{
    console.log ( message );
}

}
